This invention relates generally to a baler for forming cylindrical bales of crop material, commonly referred to as a round baler. More particularly, this invention is directed to improved roll stripping apparatus for round balers using rolls in the formation of bales.
Prior art balers of this type generally have a bale forming chamber defined by an apron comprising an array of side-by-side belts, transverse slats trained on chains, a plurality of rolls or a combination of these various elements, e.g., rolls and belts. Crop material, such as hay, is picked up from the ground as the baler traverses the field, fed into a fixed or adjustable chamber where it is rolled up to form a compact cylindrical bale. The formed bale is wrapped in its compacted form while still inside the bale forming chamber by net, twine or the like, prior to ejecting the bale from the chamber onto the ground for subsequent handling.
Round balers of the general type mentioned above comprising a chamber defined at least partially by a plurality of side by side, longitudinally extending belts supported on a plurality of transverse rollers have encountered problems of varying degree caused by build-up of stray crop material on the rolls. Random debris from crop material that is being formed in the chamber passes through the spaces between the belts and becomes entrapped in the area adjacent the guide rolls or drive rolls around which the belts are traversing during operation of the baler. When the crop material being baled is damp and particularly if it is a short cut of grass crop an unwanted build-up of debris tends to form on the roll which is detrimental to proper belt tracking on the rollers. Eventually, if permitted to go uncorrected, serious problems may occur from poor tracking eventually leading to binding of the belts and even eventual belt deterioration and breakage.
A number of prior art solutions to reduce or overcome these problems have been proposed. For example, U.S. Pat. No. 4,581,879, issued in the name of H. D. Anstey on Apr. 15, 1986 discloses an anti-wrap attachment for round balers directed to the avoidance of stray hay wrapping around the ends of a roll in the area of the bearings. Anstey shows a spiral welded or a roll in combination with a scraper mounted with its edge in the vicinity of the roller to remove crop debris being carried around the surface of the roll. Scraping devices in combination with round baler rollers are also shown in various other prior art balers, e.g., U.S. Pat. No. 4,436,027, issued in the name of John H. Freimuth et al on Mar. 13, 1984, shows a stripper bar for preventing crop debris build-up on a floor roller in a round baler. U.S. Pat. No. 4,155,298 issued in the name of M. V. Gaeddert on May 22, 1979, is another example of a prior art baler in which a roll scraper is employed to discourage the build-up of unwanted crop material around the surface of a roll used during the formation of hay into a cylindrical bale.
Although the prior art arrangements of removing debris build-up on rollers has met with varying degrees of success, the root of the problem is the fact that material is permitted to reach the stage at which a scraping device becomes necessary. Thus, prevention of build-up as well as a cooperating scraper are important interrelated aspects of reliable round baler performance to which the present invention is devoted.